Optical interconnects offer promising solutions to data transmission bottlenecks in supercomputers and in data-centers as well as other applications. Adopting higher channel data rates can greatly reduce the complexity in optical communication systems and/or further improve interconnect capacity and density.
The most important requirement on the driver amplifier is the output voltage swing. The state-of-the-art driver amplifier in CMOS/BiCMOS can output 3 Vpp at 40 Gb/s, consuming 1.35 W DC power. See for example, C. Knochenhauer, J. Scheytt, and F. Ellinger, “A Compact, Low-Power 40-GBit/s Modulator Driver With 6-V Differential Output Swing in 0.25 um SiGe BiCMOS,” Solid-State Circuits, IEEE Journal of, vol. 46, no. 5, pp. 1137-1146, 2011.
At higher data rates it is difficult to maintain or improve the available drive voltage without substantial advances in the fabrication process. This trend is at odds with the increasingly higher drive voltage required by modulators at higher speed.
There is a need for improved drivers for use in optical data handling systems.